1. Field of the Invention:
This invention relates to a machine and method for sheathing bales of farm crop, e.g. hay, and particularly to features that are directed to adapting the bale sheathing concept to commercial application.
2. Background of the Invention:
Protecting a harvested farm crop from the elements is beneficial to the user. Such is the case for protecting baled material such as cattle fodder. The commonly assigned co-pending U. S. patent application Ser. No. 07/760,701 titled Bale Sheathing Method and Apparatus discloses a machine for inserting bales of material in a tubular resilient plastic sheath or bag.
The machine is arranged to stretch or enlarge the sheath radially to increase its opening to facilitate placement of the bales within the sheath. The sheath, which is initially open ended, is axially gathered into a ring-like configuration. The ring shaped sheath is placed on the sheathing machine with the sheath encircling a lower support pan and a series of movable posts cooperatively arranged in a circular pattern. The movable posts are mounted to a support frame which is of a circular configuration. The movable posts are strategically positioned at selected circumferentially spaced positions supported by the circular frame. The posts are mounted for radial movement by individual cylinders. Movement of the posts radially outward in conjunction with the lower support pan stretches the sheath to enlarge its opening. The sheath is, in effect, enlarged upward and laterally with respect to the lower support pan. The shape of the sheath opening is determined by the posts and assumes the shape of a polygon, with the posts residing in the corners of the polygon.
A guide structure supported on a movable carriage sequentially lifts and directs a plurality of cylindrically shaped bales through the circular frame and thus into the bag or sheath as the machine travels down a row of bales. The circular frame is dimensioned to encircle the largest sheath (and the posts supporting the sheath) in its stretched condition. Since the circular frame encircles a polygon (i.e., the stretched sheath) the overall dimension of the frame is larger that the stretched sheath which establishes the overall dimensions of the machine. However, it is the polygon tunnel defined by the stretched sheath that dictates the size of the bale to be sheathed rather than the circular configuration of the support frame. In brief, the circular frame supports a polygon which envelopes a cylinder (or near cylinder) and the diameter of the frame substantially exceeds the diameter of the bales. It is desirable to have the machine reduced in overall width, more in line with the diameter of the largest bale that is being accommodated. The reduced width is desirable for shipping and for road travel between job sites.
A further problem exists with respect to the prior bale bagging machines. The bales, which weigh hundreds of pounds each exert large forces on the sheathing machine as the machine progresses down the bale row. The bale is, in effect lifted by the guide structure when it is first engaged by the machine. The large weight of the bale on the guide structure tends to cause a deflection, in effect urging the machine to tilt forward. If the support wheels are positioned behind the guide structure, the guide structure may be tilted toward the ground and in many instances may cause the guide structure to gouge into the ground. The opposite affect is experienced as the bales pass through the frame, i.e., the weight is shifted to the rear of the machine. If the support wheels are positioned under the guide structure, the guide structure can be tilted upward and prevent engagement of a subsequent bale.
The objective of the present invention(s) is to reduce overall width and provide a design that avoids the tilting problem.